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Blood test. Multi-pipette puts blood samples into a multi-well sample tray during an Enzyme-Linked ImmunoSorbent Assay (ELISA) test for antibodies to viral diseases such as AIDS (Acquired Immune Deficiency Syndrome) and Hepatitis B & C. In the ELISA test, blood serum of the patient is added to burst T-cells of blood which have been infected by disease. Viral antibodies in the serum of the patient bind to viral antigens from the T-cells. When labelled antihuman immunoglobulin is added, a colour change occurs if viral antibodies are present.